1. Field of the Invention
The present invention relates to an image processing apparatus, a communication device and system thereof, and particularly to a video communication device for displaying image data and a system incorporating such a device.
2. Related Background Art
If digital video data is reproduced as a dynamic image by a computer, in the prior art a digital video data file is successively read and displayed on the screen of a monitor after a file is decompressed in case it is compressed. Therefore, normally only one image at a time in a video data file can be seen. According to the prior art, video data consisting of different files cannot be reproduced and displayed continuously.
For instance, if the past video data stored in a video server is desired to be read when the current image provided by a video camera connected to a computer in a network is communicated to another computer via the network and is recorded in the video server in the network as a file divided every given period of time, repetitive work in which another file is read after reading a file is completed is required.
To know how an image changes after a given time elapses when a reproduced image is seen, an operation for reading, reproducing and displaying another file is required if the image exists in another file, and manual setting of time is required even if the image exists in the same file.
Furthermore, in a video conference system and a supervisory control system for monitoring a remote site, an image provided by a video camera is transmitted and displayed via a network.
In the meantime, a system exists in which an image provided by a video camera is digitized, compressed according to an image coding scheme such as Moving Picture Experts Group (MPEG) and Joint Photographic Coding Experts Group (Motion JPEG) if necessary, and stored in an image database.
However, if the past image of the current one provided by a camera is retrieved because a system for transmitting and displaying a remote image and a system retrieving and displaying an image stored in an image database are separate, both systems must be activated individually.
Also, as both systems are separate, an image cannot be retrieved and displayed continuously from the past to the present and the operations are also inconsistent.